MACTek BULLET™ – User Manual
DM1101010UAB
Copyright 2009-2010
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Direct Powered – Max Bandwidth
This allows for the maximum WirelessHART bandwidth possible and assumes that the
direct power source can supply maximum power.
Direct Powered – Power Save
This assumes that the direct power source is limited and will limit the amount of
WirelessHART packets to a small amount to conserve power
Note: The Bullet will power up and begin to operate with any valid power installation,
regardless of what the Adapter Power setting is configured as. This allows for the user
to change this setting even if it is configured incorrectly, however any changes to this
should be performed before the Bullet has joined the WirelessHART network. If this
power setting set different than how the Bullet is actually powered (such as a Direct
Powered setting is selected but the unit is actually loop powered), the system operation
is not guaranteed and it is possible that the Bullet will reset due to insufficient power
once connected to the WirelessHART network.
Note: The unit can be both Direct Powered and wired in series with the loop. When
configured in any of the Direct Powered modes, there will be an insertion voltage drop of
1.0V if the Bullet is also wired in series with the loop.
Field Device Power Control
When used in a direct power configuration, the Bullet can activate a switchable
terminating resistor between the HART and the RETURN signal wires. This can
eliminate the need for an external terminating resistor in some installation and also
allows for the field device power to be switchable and controlled automatically by the
Bullet.
The parameter “Field Device Power Control” can be set to three different states: Off, On,
or Switching.
Off:
The Field Device Power Control switch is never connected
On:
The Field Device Power Control switch is always connected
Switching:
The Bullet will automatically control the operation of the Field Device Power
Control switch.
Field Device Power Control – Switching Mode
When the Bullet is used in the “Field Device Power Control Switching” mode, the Bullet
will control this switch to power on and off HART Field Devices as needed by the
network operation. This is useful when running off a limited power source, such as an
